Handling cane juice



Oct. 16, 1928.

E. E. HARTMANN HANDLING CANE JUICE Filed June 15, 1926 ATTORNEY PatentedOct. 16, 1928.

UNITED STATES PATENT OFFICE- ERNEST EDWARD HARTMANN, OF NEW YORK, N.Y.,- ASSIGNOR TO PETR-EE & DORE ENGINEERS, INC., 01 NEW YORK, N. Y., ACORPORATION OF CUBA.

HANDLING CANE JUICE.

Application filed June 15, 1926. serialno. 116,079.

The general object of my present invention is to provide an improvedmethod of and apparatus for extracting the sugar content from, anddisposing of the precipitate commonly called mud, collected in thesettling and decantation of sugar cane juice.

The invention is characterized by the provisions made for eifecting anintimate admixtureof the mud with the material forming the bagasseblanket passing through the later stages of the cane milling circuit soas to insure a more thorough retention of the mud in the bagasse than ispossible when the mud is fed onto the top of the bagasse blanket as itis in the ordinary practice of the Petree process disclosed in PatentNo. 1,266,882, anted May 21, 1918.

I have und that the degree of retention of the mud in the bagasseblanket is in a general way proportional to the aggregate surface areaof the bagasse fibre particles to which the insoluble constituents ofthe mud have an opportunity to adhere. With the bagasse in a finelysubdivided condition as it is desirable for the best results in thepractice of the Petree process, mud returned to the top surface ofthebagasse blanket tends to separate immediately into clear liquid absorbedby the bagasse blanket and a slimy layer retained on top of the blanket.Under such conditions the excess of surface of the bagasse particlesexposed'to contact with the bagasse fibres is relatively small, and whenthe blanket with its slimy top layer reaches the next mill in thecircuit, a considerably larger portion of the solid portion of the mudis pressed out of the bagasse than is separated from the latter if themud is mechanically mixed with the material forming the bagasse blanketinstead of being merely deposited on top of the latter.

The same general advantage of mechanically mixing the mud and bagasse isobtained with coarsely divided bagasse as with finely divided bagasse.If the baggasse is course the bagasse blanket structure may be quiteopen, and when the mud is simply deposited on top of the bagasseblanket, the insoluble particles may penetrate quite deeply into thebagasse blanket, but the amount of bagasse fibre brought into contactwith the solid particles of the mud is not greatly increased thereby, assuch portions of the solid particles of the mud as enter the blanket arethen largely held in pockets or cells in the blanket, and toa-considerable extent are pressed out of the latter in thesubsequentstages of the milling operation.

In accordance with the present invention, the milling circuit isequipped with provisions for mechanically agitating the bagasse blanketas, or after the mud is returned to the milling circuit and before themudand the bagasse after being brought together, are subjected to afurther juice expressing action.

' These and other features of novelty which characterize my inventionare pointed out with particularity in the claims annexed to and orming apart of this specification. For a better understanding of the invention,however, its advantages and specific objects attained with its use,reference should be had to the accompanying drawings and descriptivematter in which I have illustrated and described preferred embodimentsof my invention.

- In the drawings:

Fig. 1 is a diagrammatic illustration of a three mill crushing plant;

a Fig. 2 is a side view of the mechanical mixing arrangement;

Fig. 3 is an elevation of the rake; and

Fi 4 is a modified arrangement for driving t 1e rake.

The apparatus diagrammatically shown in Fig. 1, includes a three millcrushing plant which consists of a primary mill A,

a secondary 'mill B, and a third mill C;

The rich juice from the mill A is screened at D, collected and limed inthe tank E, and

transferred by the pump F through the heater G to the settling vessel H.The clarified juice from the settling vessel H passes to the evaporatingplant by the pipe line J, and the mud passes by the pipe line K to thetank L which receives the screened thin juice from the mill 13 via thescreen M. The mud and thin juice are limed in the tank L and are thenpassed by the pump N to the heater 0 and thence to the settling vesselP. The clarified juice from the settling vessel P goes by the pipe lineQ, to the tank E, where it mixes with the rich juice and the mixture isdefecated. The mud from the settling vessel P is returned to the millingcircuit through the pipe line B. at a point between the mills A and B.Maceration water is applied to the bagasse between the mill B and themill C, and the thin juice from the mill C may be applied either withthe mud from the settling vessel P, or separately, to the bagasse. In sofar as above described, the apparatus shown is constructed and operatedin accordance with the usual practice in plants in which the Petreeprocess is employed.

In accordance with the present invention,

the mud returned to the milling circuit is the bagasse to the mill B.The mud coming back to the milling circuit from the settling tank Pthrough the pipe R'is received by a mud ipe S which discharges into atrough 2 provided with openings S from which the mud drops into contactwith the bagasse while the latter is being agitated by the arms T of theagitator T. As shown, the trou h S is supported by arms IV and W" of arams worl: W. In the construction illustrated the agitator blades T areof equal length and are secured to, and spaced angularly about as wellas longitudinally of the mixer shaft T, the angular displacement oflongitudinally adjacent blades being 45 in the construction shown. Theshaft T is supported by bearings T in the frame W, and driven in thedirection of the arrows in Fig. 2, by the sprocket and chain or otherdriving belt T from the roller A secured on the end of the shaft T. Theendless belt conveyor V, driven by the sprocket wheel V and passing overthe pulley Wheels V V and V is supported at its edges by the angle ironsW secured to the side frames W. The side frames W extend upward andserve to prevent the bagasse from dropping over the sides of the beltconveyor.

In the intended operation of the apparatus as shown in Fig. 2 the mixerarms T engage the bagasse while moving in a direction opposite to thebagasse stream. The arms T are of sufficient length and so ar .rangedthat the greater part of the bagasse is collected bythe arms, passedunder the trough openings S and discharged by gravity onto the conveyorV at the opposite side of the rotating mixer T from the mill A. Thisagitation of the bagasse mass while the latter is passing under theopenings S insures a much greater surface area of bagasse particles incontact with the mud flowing .down from the openings S than would be hadif the mud fell directly onto the top of an unagitated bagasse blanket.Having been mixed with the mud, the bagasse is carthe roller A throughthe sprocket chain or other driving belt 1 so that the mixer arms engagethe bagasse while moving in the same direction as the moving bagassestream. In the operation of this form of the invention the mud andbagasse are Worked into intimate contact.

The advantages of mixing the mud and I bagasse obviously donot dependprimarily on whether the mud returned has or has not been subjected tothe special treatment characteristic of the"Petree process before itsreturn.

While in accordance with the provisions of the statutes I haveillustrated and described the best form of embodiment of my inventionnow known to me, it will be apparent to those skilled in the art thatchanges may be made in the form of the apparatus disclosed withoutdeparting from the spirit of my invention as 'set forth in the appendedclaims and that in some cases certain features of my invention may beused to advantage without a corresponding use of other features.

Having now described my invention what I clalm as new and desire tosecure by Letters Patent, is Y 1. In the extraction of sugar cane juiceby successively crushing and macerating sugar cane, defecating theextracted products, and returning the defecation mud to the millingcircuit, the improvement which consists in stirring the bagasse toincrease the surface area of bagasse particles brought into contactwith'the insoluble portion of the mud.

2. In the extraction of sugar cane juice by successively crushin andmacerating sugar cane, defecating t e extracted products and returningthe defecation mud to the milling circuit, the improvement whichconsists in mechanically mixing the mud with the bagasse to increase theretention of the 1 cally mix defecation mud with the bagasse in anintermediate portion of the milling circuit.

4. In apparatus for extracting sugar cane juice from sugar cane, thecombination with a milling circuit comprising a series of mills and atravelling conveyor for transporting bagasse from one mill to another inthe circuit, of means adapted to mix defecation mud with the bagasse inthe milling circuit comprising a mud discharger and a rotating agitatorabove said conveyor.

5. In apparatus for extracting sugar cane juice from sugar came, thecombination of a pair of crushing mills and means for conveying bagassefrom one of said mills to the other, of means adapted to add defecationmud to and mix it with the bagasse as the latter is being conveyed fromthe one millto the other.

6. In a sugar mill, the combination of a pair of mills and means formoving a bagasse blanket from one mill to the other, of means for addingdefecation mud to the moving bagasse, an agitator for mixing the mud andbagasse comprising a rotating shaft extending transversely to thedirection of blanket movement and carrying arms dipping into the blanketpathway.

7. In a sugar mill, the combination of a pair of crushing mills, ofmeans for mixing defecation mud with the bagasse passing from one ofsaid mills to the other comprising a continuous conveyor transferringagasse between adjacent mills, a defecation mud container having aperforated bottom and located above said conveyor, and a rotating shafthaving a series of arms arranged to agitate the bagasse.

Signed at New York city, in the county of New York and State of ERNESTEDWARD HABTMANN.

New York, this 12th day of June, A. D. 1926.

